I read the Kotaku take on the Next Box and it turns out DOA6's 4K mode (which i didn't even know was a thing) which normally runs at 30 runs at 60 on the Next Box; as long as the fps isn't capped it looks everything will run at 60 with improved load times
Digital foundry showed off a clip of DOA6 in the 4K mode running pretty solid at 60fps..DOA5 has nowhere to go without a patch (not happening) as the performance targets are already hit. I guess even faster loading would be it there.